{"id":228664,"date":"2025-09-15T12:06:11","date_gmt":"2025-09-15T12:06:11","guid":{"rendered":"https:\/\/www.europesays.com\/us\/228664\/"},"modified":"2025-09-15T12:06:11","modified_gmt":"2025-09-15T12:06:11","slug":"the-tiny-cosmic-keyholes-that-could-send-asteroids-back-to-earth","status":"publish","type":"post","link":"https:\/\/www.europesays.com\/us\/228664\/","title":{"rendered":"The Tiny Cosmic \u201cKeyholes\u201d That Could Send Asteroids Back to Earth"},"content":{"rendered":"

\t\t\"Asteroid<\/a>Asteroid deflection could backfire if the impact shoves the rock into a cosmic keyhole, a hidden trapdoor in space. Researchers are developing probability maps to guide safer strikes and prevent a delayed disaster. Credit: Rahil Makadia<\/p>\n

Deflecting an asteroid isn\u2019t just a matter of smashing into it with a spacecraft. If the strike happens in the wrong place, it could nudge the space rock into a tiny gravitational \u201ckeyhole,\u201d a hidden gateway that steers it back onto a collision course with Earth.<\/strong><\/p>\n

Building on lessons from NASA\u2019s DART mission, researchers are now creating detailed maps of asteroid surfaces to find the safest spots for impact. By aiming precisely, they hope to ensure humanity can push dangerous asteroids away without accidentally setting up a future catastrophe.<\/p>\n

Smashing Asteroids With Precision<\/p>\n

Selecting the right spot to smash a spacecraft into the surface of a hazardous asteroid to deflect it must be done with great care, according to new research presented at the EPSC-DPS2025 Joint Meeting this week in Helsinki. Slamming into its surface indiscriminately runs the risk of knocking the asteroid through a \u2018gravitational keyhole\u2019 that sends it back around to hit Earth at a later date.<\/p>\n

\u201cEven if we intentionally push an asteroid away from Earth with a space mission, we must make sure it doesn\u2019t drift into one of these keyholes afterwards. Otherwise, we\u2019d be facing the same impact threat again down the line,\u201d said Rahil Makadia, a NASA Space Technology Graduate Research Opportunity Fellow at the University of Illinois at Urbana-Champaign, who is presenting the findings at the EPSC-DPS2025 meeting.<\/p>\n

\"NASA<\/a>This illustration depicts NASA\u2019s Double Asteroid Redirection Test (DART) spacecraft prior to impact at the Didymos binary asteroid system. Credit: NASA\/Johns Hopkins APL\/Steve Gribben
\nLessons From NASA\u2019s DART Mission<\/p>\n

NASA\u2019s DART, the Double Asteroid Redirection Test mission, struck the small asteroid Dimorphos, which is in orbit around the larger asteroid Didymos, in September 2022. DART was a \u2018kinetic impactor\u2019 \u2013 effectively a projectile that slammed into the asteroid with enough energy to nudge it into a new orbit, thereby proving that it is possible to deflect an asteroid that could be on a collision course with Earth.<\/p>\n

A European Space Agency mission called Hera will follow up on the DART impact when it reaches Didymos and Dimorphos in December 2026.<\/p>\n

Keyholes: Gateways to Future Impacts<\/p>\n

Where DART struck on Dimorphos was of relatively little concern, since the Didymos system is too massive to be deflected onto a collision course with Earth. However, for another hazardous asteroid orbiting the Sun, even a small variation in its orbit could send it through a gravitational keyhole.<\/p>\n

The keyhole effect revolves around a small region of space where a planet\u2019s gravity can modify a passing asteroid\u2019s orbit such that it returns on a collision course with that planet at a later date. In this way, a gravitational keyhole unlocks more dangerous orbits.<\/p>\n

Should a kinetic impactor mission similar to DART nudge a hazardous asteroid so that it passes through a gravitational keyhole, then it only postpones the danger.<\/p>\n

\u201cIf an asteroid passed through one of these keyholes, its motion through the Solar System would steer it onto a path that causes it to hit Earth in the future,\u201d said Makadia.<\/p>\n

\"Asteroid<\/a>One of the keyhole probability maps of the asteroid Bennu, The crosshair corresponds to the location on the surface that minimises the asteroid impact hazard after deflection. The maps assume a 25-metre targeting uncertainty for a kinetic impactor mission. As a result, deflection sites that could result in the kinetic impactor missing as a result of this uncertainty are not considered and form a grey boundary around the targetable region of the asteroid. Credit: Rahil Makadia
\nThe Challenge of Picking the Right Impact Point<\/p>\n

The trick, therefore, is to find the best spot on the surface of an asteroid to impact with a spacecraft so that the chances of pushing it through the keyhole are minimized.<\/p>\n

Each point on the surface of an asteroid has a different probability of sending the asteroid through a gravitational keyhole after deflection by a kinetic impactor. Makadia\u2019s team has therefore developed a technique for computing probability maps of an asteroid\u2019s surface. Their method uses the results from DART as a guide, although each asteroid, with its own characteristics, will be subtly different.<\/p>\n

Ground vs. Space-Based Observations<\/p>\n

The asteroid\u2019s shape, surface topology (hills, craters, etc.), rotation, and mass all must be determined first. Ideally, this would be done with a space mission to rendezvous with the asteroid, producing high-resolution images and data. However, this might not be possible for all threatening asteroids, particularly if the time between discovery and impact on Earth is short.<\/p>\n

\u201cFortunately, this entire analysis, at least at a preliminary level, is possible using ground-based observations alone, although a rendezvous mission is preferred,\u201d said Makadia.<\/p>\n

Protecting Earth in the Long Run<\/p>\n

By computing the subsequent trajectory of the asteroid following a kinetic impact, and seeing which trajectories would be the most dangerous, scientists can calculate where the safest location to strike on the asteroid\u2019s surface will be.<\/p>\n

\u201cWith these probability maps, we can push asteroids away while preventing them from returning on an impact trajectory, protecting the Earth in the long run,\u201d said Makadia.<\/p>\n

Reference: \u201cKeyhole-Based Site Selection for Kinetic Impact Deflection of Near-Earth Asteroids\u201d by Rahil Makadia, Steven Chesley, Davide Farnocchia and Siegfried Eggl, 8 July 2025, EPSC-DPS Joint Meeting 2025.
DOI: 10.5194\/epsc-dps2025-77<\/a><\/p>\n

The work was funded by a NASA Space Technology Graduate Research Opportunities (NSTGRO) award, NASA contract No. 80NSSC22K1173.<\/p>\n

Never miss a breakthrough: Join the SciTechDaily newsletter.<\/a><\/b><\/p>\n","protected":false},"excerpt":{"rendered":"Asteroid deflection could backfire if the impact shoves the rock into a cosmic keyhole, a hidden trapdoor in…\n","protected":false},"author":3,"featured_media":228665,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[24],"tags":[19776,123571,123572,15477,159,783,67,132,123573,68],"class_list":{"0":"post-228664","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-space","8":"tag-asteroid","9":"tag-europlanet","10":"tag-nasa-dart","11":"tag-planetary-defense","12":"tag-science","13":"tag-space","14":"tag-united-states","15":"tag-unitedstates","16":"tag-university-of-illinois-at-urbana-champaign","17":"tag-us"},"share_on_mastodon":{"url":"https:\/\/pubeurope.com\/@us\/115208230340422199","error":""},"_links":{"self":[{"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/posts\/228664","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/comments?post=228664"}],"version-history":[{"count":0,"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/posts\/228664\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/media\/228665"}],"wp:attachment":[{"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/media?parent=228664"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/categories?post=228664"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/tags?post=228664"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}